Aballoon is filled with helium at sea level the volume is measured to be 3.1 liters at a pressure of 0.97 atmosphere. if the balloon is released it drifts upwards. at height of 4 kilometers the pressure is measured to be 0.61 atmospheres. what is the volume of the balloon?

Achemistry student weighs out 0.306 g of citric acid (h3c6h5o7), a triprotic acid, into a 250 ml volumetric flask and dilutes to the mark with distilled water. he plans to titrate the acid with 0.1000 m naoh solution. calculate the volume of naoh solution the student will need to add to reach the final equivalence point. be sure your answer has the correct number of significant digits.